F.A.Q

Whether it be Solar Energy, Solar Panels, or Renewable Energy in general, there are always questions to be asked. Here we have attempted to answer as many as possible.

Q: How do we get electricity from the sun?A: Sunlight is made up of small particles of energy called photons. Photovoltaic (PV) systems use semi-conducting materials such as silicon to absorb some of these photons and transfer them to electrons. This process is known as the photoelectric effect and it is the basic physical process by which PV cells convert sunlight to electricity. Special electrical properties of the PV cell – a built-in electric field – provide the voltage needed to drive the current through an external load (such as a light bulb).

Q: What does energy conversion efficiency mean?A: Energy conversion efficiency is an expression of the amount of energy produced in proportion to the amount of energy consumed, or available to a device. The Sun produces a lot of energy in a wide light spectrum, but we have so far learned to capture only small portions of that spectrum for conversion to electricity using photovoltaics. Today's commercial PV systems are about 7% to 17% efficient. By comparison, a typical fossil fuel generator has an efficiency of about 28%. However, some experimental PV cells now convert nearly 40% of the energy in sunlight to electricity.

Q: Why should I use renewable energy generated electricity?A: For a growing number of users, particularly those who are environmentally aware, renewable energy is the clear choice. Solar provides sustainable energy, operates silently, produces no toxic emissions or greenhouse gases, and causes no hazardous waste. Renewable energy systems generate electricity using the Sun's free energy, wind, or water, so the ongoing costs are minimal. Moreover, continued R&D means installation costs are gradually being reduced. Some people would rather invest capital on an energy-producing improvement to their property than continually send money to a power company. Others like the security of reducing the amount of electricity they buy from power utilities, because it makes them less vulnerable to power outages and future increases in the price of electricity.

Q: Can I use renewable energy to power my home?A: Renewable energy can be used to power your entire home's electrical systems, including lights, cooling systems, and appliances. For example, solar systems today can be blended easily into both traditional and non-traditional homes. The most common practice is to mount modules onto a north-facing roof or wall (in the southern hemisphere). For an additional aesthetic appeal, some modules resemble traditional roof shingles and tiles or can be built right into glass skylights and walls.

Q: Can I use Renewable energy to power my business?A: Renewable energy systems can be blended into virtually every conceivable structure for commercial buildings. You will find PV being used outdoors for security lighting as well as in structures that serve as covers for parking lots and bus shelters, generating power at the same time. Architects can use building-integrated PV to design buildings that are environmentally responsive, aesthetically pleasing, and produce their own power. Building-integrated PV provides a dual-use building material, reduces renewable energy system costs by using the building as the mounting or support structure, and reduces utility bills through on-site power production.

Q: How much can I save by using a renewable energy system?A: A 10% efficient PV system will generate about 180 kilowatt-hours per square meter. A PV system rated at 1 kilowatt will produce about 1800 kilowatt-hours a year. Allowing for a loss of efficiency of less than 1% per annum, such a PV system could generate close to 36,000 kilowatt-hours of electricity over 20 years and close to 54,000 kilowatt-hours over 30 years. This means that a solar system generates more than US$10,000 worth of electricity over 30 years.